class_docstr: An as-of-yet unset attribute or unprovided default parameter.
code: def __repr__(self):
      return "<unset>"
  
imports: import itertools
  import json
  import pkgutil
  import re
  from jsonschema.compat import MutableMapping, str_types, urlsplit
label_desc: Use image node_id 1 for calling the Unset obj's underlying member method code with example usage: obj.__repr__() and returns: str